1. Field of the Invention
The present invention relates to a composite service control system that predicts and resolves a conflict between applications that independently developed and operated. The system classifies a conflict as an explicit conflict that occurs inevitably when the applications are executed, and an implicit conflict that occurs conditionally depending on the execution flow of the applications. And when a new application is developed and registered to be deployed to the system, the system predicts a conflict based on the implicit conflict and the explicit conflict and reports a conflict to establish conflict resolution policies. When the applications are in service, the system detects and resolves the predicted conflict using the established conflict resolution policies.
2. Description of the Related Art
Development of information and communication technologies enables various supplementary services in addition to primary services such as a voice call service, and a short message service on a communication network. A number of the supplementary services gradually increases and the supplementary services implements various business logic, and thus, it is important to operate the service without a conflict between the services.
Particularly, various supplementary services dynamically using a profile, a presence, a multimedia, and the like are provided in an Internet Protocol (IP) network environment, and a concept of a composite service that provides a new enhanced service by combining existing services is introduced. It is important for the composite service to promptly develop and introduce a new service compared with a conventional voice service environment where a relatively limited number of supplementary services are provided.
However, development and deployment of the composite service have two major difficulties.
One difficulty relates to how to easily and promptly develop and provide the new service.
For this, the composite service introduces a technology that provides an application programming interface (API) as a web interface, the API being required for abstracting a function of a network, such as a parlay-X, and controlling a service.
Another difficulty relates to how to prevent the conflict between services, since there may be services pursuing inconsistent objectives or competing for an identical network resource when various services exist. For this, ITU-T defines a ‘service capability interaction manager’ function to prevent the conflict between services. However, only the logical function is defined and a method of embodying the function is not provided.
It has been well known that the conflict between the services may occur when various supplementary services exist in a communication network, and this is referred to as a ‘feature interaction’ problem. A representative example is a situation where ‘call forwarding and a call waiting’ exist together. This situation may be a problem when a user simultaneously uses both services, that is, when a new call is received while the user still on the phone. In this instance, an call exchange system may not determine whether to perform a call forwarding service that redirect the call to an predetermined phone number or to perform a call waiting service that enables the user to come and go between the ongoing call and the new call by pressing a hook flash. The conflict may be caused by incompatibleness of the objectives of the services triggered at an identical precondition or competition to use an identical resource.
In addition, the composite service that configures the new service by combining existing services may have a high possibility of conflict since the services comprising the composite service interact with each other, and may have difficulty in predicting the conflict in advance to resolve the conflict.
Conventionally, a concept of a service broker has been used for controlling an interaction of the composite service in a voice communication network. A service broker scheme monitors various events such as a message generated in a network and distributes the events to an appropriate application, thereby embodying the composite service. According to the service broker scheme, when the composite service is embodied by using the existing application, a developer of the composite service may make a composite service logic processing each event and may load the composite service logic to the service broker. In this instance, the service logic contained in the service broker is required to solve a possible conflict due to a new composition, by the service logic alone. Also, since all the composite service logic is contained and executed in the service broker, the service broker may centrally control execution of all the composite application.
As described above, in the service broker scheme, a composite application writer may require detailed information with respect to operations of all services, and may be required to embody an exact service logic that prevents or processes a conflict based on the detailed information. In general, it is significantly difficult to obtain and analyze the information, and also many tests and many trials and errors are required to determine that an added service does not cause a conflict. Also, since the composite service logic is executed in the service broker, there is a problem in that the service broker may have a performance burden. Accordingly, the present invention proposes a new technology that uses a concept of the composite service and predicts a conflict between applications to prevent the conflict between the applications in advance.